Off-wall electrode device and methods for nerve modulation

Abstract

Systems for nerve modulation through the wall of a blood vessel are disclosed. An example system for nerve modulation may include an elongate member extending along a central elongate axis and having a proximal end and a distal end. The elongate member may have a radially expandable member disposed proximate the distal end. A tubular sheath may be cooperatively engaged with the expandable member such that the expandable member is collapsed when in the sheath and can expand when moved distally relative to and past a distal end of the sheath. The expandable member may include a plurality of electrodes and a plurality of spacer struts. Each spacer strut may be configured such that when the self-expanding member is in an expanded state the spacer strut extends out radially further than the electrodes from the central elongate axis.

What is claimed is: 
     
       1. A system for nerve modulation through a wall of a blood vessel, comprising:
 an elongate member extending along a central elongate axis and having a proximal end and a distal end, the elongate member having a radially expandable member disposed proximate the distal end; and 
 a tubular sheath cooperatively engaged with the expandable member such that the expandable member is not expanded when in the tubular sheath and can expand when moved out of the tubular sheath, 
 the expandable member comprising a plurality of electrodes on an expandable frame wherein each of the plurality of electrodes has a first surface that is entirely electrically insulated and faces radially outwards relative to the expandable member and a second surface that is electrically conductive surface that and faces radially inwards towards a central longitudinal axis of the expandable member. 
 
     
     
       2. The system of  claim 1 , wherein the expandable frame provides a conductive path to the plurality of electrodes and wherein the expandable frame is electrically insulated. 
     
     
       3. The system of  claim 1 , wherein the expandable member is self-expanding. 
     
     
       4. The system of  claim 1 , wherein at least some of the plurality of electrodes and the expandable frame are formed from the same material. 
     
     
       5. The system of  claim 1 , wherein the plurality of electrodes are disposed on the expandable frame in an axially and circumferentially staggered pattern. 
     
     
       6. The system of  claim 1 , wherein the expandable frame and the first surface of each of the plurality of electrodes is covered with an electrically insulative material. 
     
     
       7. The system of  claim 1 , wherein the expandable frame extends to the proximal end of the elongate member. 
     
     
       8. The system of  claim 1 , wherein the plurality of electrodes are each connected to an independent power supply. 
     
     
       9. A system for nerve modulation through a wall of a blood vessel, comprising:
 an elongate member extending along a central elongate axis and having a proximal end and a distal end, the elongate member having a radially expandable member disposed proximate the distal end; and 
 a tubular sheath cooperatively engaged with the expandable member such that the expandable member is not expanded when in the tubular sheath and can expand when moved out of the tubular sheath, 
 the expandable member comprising a plurality of non-contact electrodes on an expandable frame, wherein each of the plurality of non-contact electrodes has a single electrically conductive surface, wherein the expandable member is configured such that when the expandable frame is expanded and in contact with a blood vessel wall, the electrically conductive surface of each of the plurality of non-contact electrodes does not contact the blood vessel wall and faces radially inward towards a central longitudinal axis of the expandable member. 
 
     
     
       10. The system of  claim 9 , wherein the expandable frame is non-conductive, and conductor wires connect the plurality of non-contact electrodes to a conductor attached to the proximal end of the expandable frame. 
     
     
       11. The system of  claim 9 , wherein the expandable member is self-expanding. 
     
     
       12. The system of  claim 9 , wherein at least some of the plurality of non-contact electrodes and the expandable frame are formed from the same material. 
     
     
       13. The system of  claim 9 , wherein the plurality of non-contact electrodes are disposed on the expandable frame in an axially and circumferentially staggered pattern. 
     
     
       14. The system of  claim 9 , wherein the plurality of non-contact electrodes are each connected to an independent power supply. 
     
     
       15. A system for nerve modulation through a wall of a blood vessel, comprising:
 an elongate member extending along a central elongate axis and having a proximal end and a distal end, the elongate member having a radially expandable member disposed proximate the distal end; and 
 a tubular sheath cooperatively engaged with the expandable member such that the expandable member is not expanded when in the tubular sheath and can expand when moved out of the tubular sheath, 
 the expandable member comprising an expandable frame having a plurality of widened regions axially and circumferentially staggered along the expandable frame, wherein each of the plurality of widened regions has a first completely electrically insulated surface that faces radially outwards relative to the expandable member and a second electrically conductive surface that faces radially inwards towards a central longitudinal axis of the expandable member. 
 
     
     
       16. The system of  claim 15 , wherein the expandable frame is non-conductive, and conductor wires connect the plurality of widened regions to a conductor attached to the proximal end of the expandable frame. 
     
     
       17. The system of  claim 15 , wherein the expandable member is self-expanding. 
     
     
       18. The system of  claim 15 , wherein the plurality of widened regions are each connected to an independent power supply. 
     
     
       19. The system of  claim 15 , wherein the expandable frame extends to the proximal end of the elongate member. 
     
     
       20. The system of  claim 15 , wherein the expandable frame provides a conductive path to the plurality of widened regions and wherein the expandable frame is electrically insulated.